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Derivatives (Notional Volumes of Foreign Exchange Swaps and Forward Contracts Related to Commodity Contracts) (Details) - Foreign Exchange Swaps and Forward Contracts [Member] - Fuel [Member] $ in Millions | Dec. 31, 2018 USD ($)
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2020-2023 [Member} |
Derivative [Line Items] |
Derivative, Notional Amount | $ 111
Derivative, Average Forward Exchange Rate | 1.3027
Derivative, Percent of USD Required to Purchase | 48.00%
Regulatory Deferral Hedge [Member] | 2019 [Member} |
Derivative [Line Items] |
Derivative, Notional Amount | $ 121
Derivative, Average Forward Exchange Rate | 1.1621
Derivative, Percent of USD Required to Purchase | 66.00%

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- Definition Percent of USD fuel required to purchase. + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Average contractual rate at which a foreign currency can be purchased or sold. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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